how to add to string js code example

Example 1: append string js

var s = "1"
s += "2"

Example 2: javascript add to string

var s = 'hell'
s = s + 'o'

Example 3: string concat in js

let string1 = "Hello"
let string2 = "World"

let finalString = string1 + ", " + string2 + "!" // Hello, World!